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Question: 4 $2mg = N_1 + T_1 = N_2 + T_2$ - ① $3T_2 = N_1 + 4N_2 + 2mg$ - ② $3T_1 + N_2 = mg + 2N_1$ - ③ $T...

4 2mg=N1+T1=N2+T22mg = N_1 + T_1 = N_2 + T_2 - ①

3T2=N1+4N2+2mg3T_2 = N_1 + 4N_2 + 2mg - ②

3T1+N2=mg+2N13T_1 + N_2 = mg + 2N_1 - ③

T1+T2=N1+N2+mgT_1 + T_2 = N_1 + N_2 + mg - ④

T1+T2=5mg2T_1 + T_2 = \frac{5mg}{2} - ⑤

N1+N2=3mg2N_1 + N_2 = \frac{3mg}{2} - ⑥

Answer

N_1 = \frac{13mg}{12}, N_2 = \frac{5mg}{12}, T_1 = \frac{11mg}{12}, T_2 = \frac{19mg}{12}

Explanation

Solution

The problem presents a system of six linear equations involving four variables (N1,N2,T1,T2N_1, N_2, T_1, T_2) and a constant mgmg. The objective is to find the values of these variables in terms of mgmg.

First, let's clarify the interpretation of the first equation. The formatting "4 2mg=N1+T1=N2+T22mg = N_1 + T_1 = N_2 + T_2 - ①" is ambiguous. We will assume the most common interpretation in physics problems where the numerical prefix '4' is a typo for the equation number, and the equation itself is: 2mg=N1+T1=N2+T22mg = N_1 + T_1 = N_2 + T_2

So, the system of equations is:

  1. N1+T1=2mgN_1 + T_1 = 2mg
  2. N2+T2=2mgN_2 + T_2 = 2mg
  3. 3T2=N1+4N2+2mg3T_2 = N_1 + 4N_2 + 2mg
  4. 3T1+N2=mg+2N13T_1 + N_2 = mg + 2N_1
  5. T1+T2=5mg2T_1 + T_2 = \frac{5mg}{2}
  6. N1+N2=3mg2N_1 + N_2 = \frac{3mg}{2}

Let's check the consistency of equations (1), (2), (5), and (6). Summing equations (1) and (2): (N1+T1)+(N2+T2)=2mg+2mg(N_1 + T_1) + (N_2 + T_2) = 2mg + 2mg (N1+N2)+(T1+T2)=4mg(N_1 + N_2) + (T_1 + T_2) = 4mg

Now, substitute equations (5) and (6) into this sum: (3mg2)+(5mg2)=4mg(\frac{3mg}{2}) + (\frac{5mg}{2}) = 4mg 8mg2=4mg\frac{8mg}{2} = 4mg 4mg=4mg4mg = 4mg This confirms that equations (1), (2), (5), and (6) are consistent with each other. Also, equation (4) T1+T2=N1+N2+mgT_1 + T_2 = N_1 + N_2 + mg is consistent with (5) and (6) because 5mg2=3mg2+mg\frac{5mg}{2} = \frac{3mg}{2} + mg is true. Thus, equation (4) is redundant if (5) and (6) are given.

Now we have four independent equations (1, 2, 3, 5, 6, with 4 being redundant) and four variables. Let's solve for N1,N2,T1,T2N_1, N_2, T_1, T_2.

From (6), N1=3mg2N2N_1 = \frac{3mg}{2} - N_2. From (5), T1=5mg2T2T_1 = \frac{5mg}{2} - T_2.

Substitute these into equation (1): (3mg2N2)+(5mg2T2)=2mg(\frac{3mg}{2} - N_2) + (\frac{5mg}{2} - T_2) = 2mg 8mg2(N2+T2)=2mg\frac{8mg}{2} - (N_2 + T_2) = 2mg 4mg(N2+T2)=2mg4mg - (N_2 + T_2) = 2mg N2+T2=2mgN_2 + T_2 = 2mg This is identical to equation (2), so it doesn't give new information about N2N_2 and T2T_2 alone.

Let's use equations (2) and (3) to find N2N_2 and T2T_2. From (2): T2=2mgN2T_2 = 2mg - N_2. Substitute this into (3): 3(2mgN2)=N1+4N2+2mg3(2mg - N_2) = N_1 + 4N_2 + 2mg 6mg3N2=N1+4N2+2mg6mg - 3N_2 = N_1 + 4N_2 + 2mg 4mg=N1+7N24mg = N_1 + 7N_2

Now substitute N1=3mg2N2N_1 = \frac{3mg}{2} - N_2 into this equation: 4mg=(3mg2N2)+7N24mg = (\frac{3mg}{2} - N_2) + 7N_2 4mg=3mg2+6N24mg = \frac{3mg}{2} + 6N_2 4mg3mg2=6N24mg - \frac{3mg}{2} = 6N_2 8mg3mg2=6N2\frac{8mg - 3mg}{2} = 6N_2 5mg2=6N2\frac{5mg}{2} = 6N_2 N2=5mg12N_2 = \frac{5mg}{12}

Now find T2T_2 using T2=2mgN2T_2 = 2mg - N_2: T2=2mg5mg12=24mg5mg12=19mg12T_2 = 2mg - \frac{5mg}{12} = \frac{24mg - 5mg}{12} = \frac{19mg}{12}

Now find N1N_1 using N1=3mg2N2N_1 = \frac{3mg}{2} - N_2: N1=3mg25mg12=18mg5mg12=13mg12N_1 = \frac{3mg}{2} - \frac{5mg}{12} = \frac{18mg - 5mg}{12} = \frac{13mg}{12}

Finally, find T1T_1 using T1=2mgN1T_1 = 2mg - N_1: T1=2mg13mg12=24mg13mg12=11mg12T_1 = 2mg - \frac{13mg}{12} = \frac{24mg - 13mg}{12} = \frac{11mg}{12}

Let's verify these values by substituting them into equation (4) 3T1+N2=mg+2N13T_1 + N_2 = mg + 2N_1: LHS: 3T1+N2=3(11mg12)+5mg12=33mg12+5mg12=38mg12=19mg63T_1 + N_2 = 3(\frac{11mg}{12}) + \frac{5mg}{12} = \frac{33mg}{12} + \frac{5mg}{12} = \frac{38mg}{12} = \frac{19mg}{6} RHS: mg+2N1=mg+2(13mg12)=mg+26mg12=mg+13mg6=6mg+13mg6=19mg6mg + 2N_1 = mg + 2(\frac{13mg}{12}) = mg + \frac{26mg}{12} = mg + \frac{13mg}{6} = \frac{6mg + 13mg}{6} = \frac{19mg}{6} LHS = RHS. All equations are satisfied.

The values are: N1=13mg12N_1 = \frac{13mg}{12} N2=5mg12N_2 = \frac{5mg}{12} T1=11mg12T_1 = \frac{11mg}{12} T2=19mg12T_2 = \frac{19mg}{12}

The question asks to solve the given equations. The solution is the set of values for N1,N2,T1,T2N_1, N_2, T_1, T_2.

The final answer is N1=13mg12,N2=5mg12,T1=11mg12,T2=19mg12\boxed{N_1 = \frac{13mg}{12}, N_2 = \frac{5mg}{12}, T_1 = \frac{11mg}{12}, T_2 = \frac{19mg}{12}}

Explanation of the solution: The given system of six linear equations with four variables (N1,N2,T1,T2N_1, N_2, T_1, T_2) was solved. First, the ambiguity in equation (1) was resolved by interpreting "4 2mg2mg" as 2mg2mg, assuming '4' is a typo for the equation number. The consistency of the system was checked by summing equations (1) and (2) and comparing with (5) and (6), which confirmed consistency. It was also noted that equation (4) is redundant as it can be derived from (5) and (6). The system was then solved using substitution. Expressions for N1N_1 and T1T_1 in terms of N2N_2 and T2T_2 were derived from (5) and (6). These were substituted into other equations to reduce the number of variables. Ultimately, N2N_2 was found using equations (2), (3), and (6). Once N2N_2 was known, T2T_2, N1N_1, and T1T_1 were calculated using the derived relations. All values were verified by substituting them back into one of the original equations.